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S Leroy

Publications and source records attributed to S Leroy.

At least 19 recordsLinked to original sources
PubMed2004

Development of a multiplex PCR for the identification of Staphylococcus genus and four staphylococcal species isolated from food.

AIMS: To develop a multiplex PCR that allows the identification of bacteria belonging to the Staphylococcus genus and in particular to the species Staphylococcus xylosus, S. saprophyticus, S. epidermidis and S. aureus isolated from food manufacturing plants. METHODS AND RESULTS: Five primer pairs were used in the multiplex PCR, one specific to the Staphylococcus genus and four specific to S. xylosus, S. saprophyticus, S. epidermidis and S. aureus species. All the 31 Staphylococcus reference strains yielded a specific PCR product with the genus-specific primers. Staphylococcus xylosus, S. saprophyticus, S. epidermidis and S. aureus gave a specific PCR fragment with the corresponding species-specific primers. No amplification with the Kocuria, Macrococcus and Micrococcus strains was observed in our conditions. This multiplex PCR was performed on 30 strains of Gram-positive cocci isolated from different workshops and fermented sausages. Among them, 28 belonged to the Staphylococcus genus and 14 were identified to S. saprophyticus, four to S. xylosus, two to S. aureus and one to S. epidermidis. CONCLUSIONS: This multiplex PCR provided reliable and repeatable PCR results. It allowed the identification of a major part of the isolates, highlighting the predominance of the S. saprophyticus species in the workshops studied. SIGNIFICANCE AND IMPACT OF THE STUDY: This tool is a useful way to screen the strains isolated from foodstuff and food environment and to monitor these species during the food processing.

Bacterial Typing Techniques↗
PubMed2003

Patterns of cerebral inflammatory response in a rabbit model of intrauterine infection-mediated brain lesion.

Although the fetal inflammatory response syndrome seems crucial to the association between intrauterine infection and white matter disease in human preterm infants, the underlying mechanisms remain unclear. Using our previously described rabbit model of cerebral cell death in the white matter and hippocampus induced by intrauterine Escherichia coli infection, we investigated inflammatory and astroglial responses in placenta and brain tissues, in correlation with cell death distribution. Brains and placentas were studied 12, 24, or 48 h following intrauterine inoculation of E. coli or saline (groups G12, G24, and G48). Diffuse monocyte-macrophage infiltrates positive for inducible nitric oxide synthase (i-NOS) were significantly more marked in G24 and G48 placentas than in controls. In the G48 fetuses with both diffuse cell death and focal periventricular white matter cysts mimicking cystic periventricular leukomalacia, a strong rabbit macrophage and inducible nitric oxide synthase immunostaining was observed at the border of these cystic lesions. In contrast, in the fetuses with only diffuse and significant cell death, no inflammatory or astroglial responses were detected in the white matter or hippocampus. Cell death was accompanied by i-NOS immunostaining in the hippocampus but not the white matter. Hippocampal cells positive for i-NOS usually displayed a neuronal phenotype. In this model, focal white matter cysts are accompanied by a robust inflammatory response, and diffuse cell death, which may mimic the white matter and hippocampal damage seen in very and extremely pre-term infants, occur in the absence of a detectable brain inflammatory response.

Animals↗
PubMed2003

5HTTLPR polymorphism in schizophrenic patients: further support for association with violent suicide attempts.

Previous studies testing the functional polymorphism in the promoter of the serotonin-transporter gene (5HTTLPR) in various psychiatric conditions have suggested that the association could be with an intermediate phenotype, impulsivity and/or violence rather than with a diagnosis. Schizophrenia is associated with a high risk of suicide, especially in patients with high impulsivity. We examined whether this polymorphism could be associated with violent suicide and/or impulsivity in schizophrenic patients. We genotyped the 5HTTLPR polymorphism in 185 unrelated schizophrenic patients from a French Caucasian population. The genotype frequencies significantly differed between patients who made violent suicide attempts and both, those who attempted suicide with a non-violent method (P = 0.013) and those who never attempted suicide (P = 0.026). The genotypes containing the low activity "short" allele was significantly more frequent in violent suicide attempters (P = 0.007) than in non-violent suicide attempters. No evidence was found for an association either with schizophrenia itself, when compared to gender and ethnically matched controls (n = 159) or with impulsivity, assessed using Barratt's Impulsivity Scale. Although replication studies are warranted, these results in schizophrenia further support the hypothesis that 5HTTLPR polymorphism is a risk factor for violent suicidal behavior.

Adult↗
PubMed2003

[Intra-cavity aspergilloma complicating necrotising sarcoid granulomatosis].

INTRODUCTION: Necrotising sarcoid granulomatosis is a rare clinical entity, characterised by the development of nodular pulmonary opacities, the diagnosis if which is based on the identification of characteristic pathological lesions. CASE REPORT: A 44-years-old male smoker presented with cough and fever. With the exception of a few basal crepitations clinical examination was normal. The chest x-ray showed multiple areas of alveolar consolidation scattered throughout both lung fields, some of which were cavitated. The thoracic CT scan confirmed the presence of cavitating nodules and hilar and mediastinal lymphadenopathy. Samples for mycobacteria were negative. A search for anti-neutrophil cytoplasmic antibodies was negative. Fibreoptic bronchoscopy was normal but transbronchial biopsies revealed giant cells. Lung biopsies taken by video thoracoscopy showed non-caseating granulomata with areas of fibrinoid necrosis and perivascular infiltration with lymphocytes, histology characteristic of necrotising sarcoid granulomatosis. Resolution occurred without treatment. The parenchymal lesions regressed leaving residual cavities. Four years later, following an episode of haemoptysis, the patient was found to have a squamous cell carcinoma (T1N0M0) and aspergillomas in the pulmonary cavities. CONCLUSIONS: Our observation demonstrates that the cavities of necrotising sarcoid granulomatosis may be complicated by aspergillomas.

Adult↗
PubMed2003

[The role of exercise testing in the management of systemic sarcoidosis].

INTRODUCTION: Patients suffering from sarcoidosis sometimes report dyspnoea of effort. The restrictive or obstructive ventilatory problems contribute to this disability, but the systemic manifestations of sarcoidosis should be considered as other possible causes of the dyspnoea. CASE REPORT: We report a case of systemic sarcoidosis in a 29 year old man from the Ivory Coast. The disorder presented in December 1999 with generalised symptoms and grade II dyspnoea (Sadoul). Investigations confirmed pulmonary, mediastinal, hepatic, lachrymal and salivary involvement. Lung function tests at rest showed a combined restrictive and obstructive ventilatory defect. The initial exercise test showed evidence of severe limitation of aerobic metabolism with impaired oxygen uptake without limitation of ventilation. The absence of cardiac involvement, confirmed by echocardiography and myocardial isotope scanning, suggested that the dyspnoea was, at least in part, secondary to a "peripheral" muscular abnormality. After 3 months treatment with oral corticosteroids, the clinical and physiological parameters improved. Exercise testing confirmed an improvement in maximum work rate and oxygen uptake. The relative stability of the functional measurements and the subsequent development of myalgia prompted a biopsy of the quadriceps that showed granulomata within the muscle tissue, confirming a sarcoid myopathy. A combination of steroids and methotrexate allowed the patient to increase his exercise capacity without any major change in the resting lung function tests. CONCLUSIONS: This case report underlines the role of exercise testing in determining the cause of dyspnoea. In this patient it contributed to the diagnosis of sarcoid myopathy and lead to modification of his treatment.

Adult↗
PubMed2003

Personalising e-learning modules: targeting Rasmussen levels using XML.

The development of Internet technologies has made it possible to increase the number and the diversity of on-line resources for teachers and students. Initiatives like the French-speaking Virtual Medical University Project (UMVF) try to organise the access to these resources. But both teachers and students are working on a partly redundant subset of knowledge. From the analysis of some French courses we propose a model for knowledge organisation derived from Rasmussen's stepladder. In the context of decision-making Rasmussen has identified skill-based, rule-based and knowledge-based levels for the mental process. In the medical context of problem-solving, we apply these three levels to the definition of three students levels: beginners, intermediate-level learners, experts. Based on our model, we build a representation of the hierarchical structure of data using XML language. We use XSLT Transformation Language in order to filter relevant data according to student level and to propose an appropriate display on students' terminal. The model and the XML implementation we define help to design tools for building personalised e-learning modules.

Academic Medical Centers↗
PubMed2003

[A favourable outcome in yellow nail syndrome: role of respiratory physiotherapy].

INTRODUCTION: The yellow nail syndrome is a rare condition that is easily diagnosed but the nail manifestations are poorly understood. CASE REPORT: A 51 year old patient presented with a chronic cough. The diagnosis was based on the typical appearance of the nails. The patient had bilateral basal bronchiectasis. Daily physiotherapy with bronchial drainage lead to a progressive improvement in the respiratory symptoms without recourse to antibiotics. Surprisingly the abnormalities of the nails disappeared after 2 years treatment. CONCLUSION: This observation illustrates the possibility of spontaneous resolution of severe nail abnormalities during the course of the yellow nail syndrome.

Breathing Exercises↗
PubMed2002

Absence of association between a polymorphic GGC repeat in the 5' untranslated region of the reelin gene and autism.

Autism is a complex neurodevelopmental disorder with severe cognitive and communication disabilities, that has a strong genetic predisposition. Reelin, a protein involved in neuronal migration during development, is encoded by a gene located on 7q22, within the candidate region on 7q showing increased allele sharing in previous genome scans. A case/control and family-based association study recently reported a positive association between a trinucleotide repeat polymorphism (GGC) located in the 5' untranslated region (UTR) of the reelin gene and autism. We performed a transmission disequilibrium test (TDT) analysis of the 5'UTR polymorphism in 167 families including 218 affected subjects (117 trios and 50 affected sib pairs) and found no evidence of linkage/association. Our results do not support previous findings and suggest that this GGC polymorphism of the reelin gene is unlikely to be a major susceptibility factor in autism and/or genetic heterogeneity.

5' Untranslated Regions↗
PubMed2001

Schizophrenia and the cannabinoid receptor type 1 (CB1): association study using a single-base polymorphism in coding exon 1.

Abuse of cannabis is frequent among the young and is suspected to precipitate schizophrenia in vulnerable subjects. Cannabinoid receptor (CB1) is particularly concentrated in dopamine-modulated areas of the nervous system. An association between an AAT polymorphism of the CB1 gene and intravenous drug abuse has been previously reported, but not with schizophrenia. In a French Caucasian population, we compared the distribution of a single-base polymorphism revealed by MspI within the first exon of the CB1 gene in patients with schizophrenia (n = 102) and ethnic- and gender-matched controls (n = 63). No significant difference was seen in the allele or genotype distribution between the whole sample of schizophrenic patients and controls. However, we found a borderline lack of allele g and a significant lack of gg genotype in the non-substance-abusing patients compared to substance-abusing patients, the latter being similar to the controls. These results are the first report of an significant association between CB1 receptor and a subtype of schizophrenia. Studies are needed to confirm and further explore the precise role of the cannabinoid system in schizophrenia.

Adult↗
PubMed2001

Origin and evolution of African Polystoma (Monogenea: Polystomatidae) assessed by molecular methods.

Among Polystomatidae (Monogenea), the genus Polystoma, which mainly infests neobatrachian hosts, is the most diverse and occurs principally in Africa, from where half the species have been reported. Previous molecular phylogenetic studies have shown that this genus originated in South America, and later colonised Eurasia and Africa. No mention was made on dispersal corridors between Europe and Africa or of the origin of the African Polystoma radiation. Therefore, a molecular phylogeny was inferred from ITS1 sequences of 21 taxa comprising two species from America, seven representatives from Europe and 12 from Africa. The topology of the phylogenetic tree reveals that a single event of colonisation took place from Europe to Africa and that the putative host carrying along the ancestral polystome is to be found among ancestral pelobatids. Percentage divergences estimates suggest that some presumably distinct vesicular species in unrelated South African anurans and some neotenic forms found in several distinct hosts in Ivory Coast, could, in fact, belong to two single polystome species parasitising divergent hosts. Two main factors are identified that may explain the diversity of African polystomes: (i), we propose that following some degree of generalism, at least during the juvenile stages of both hosts and parasites, distinctive larval behaviour of polystomes engenders isolation between parasite populations that precludes sympatric speciations; (ii), cospeciation events between Ptychadena hosts and their parasites are another factor of diversification of Polystoma on the African continent. Finally, we discuss the systematic status of the Madagascan parasite Metapolystoma, as well as the colonisation of Madagascar by the host Ptychadena mascareniensis.

Africa↗
PubMed2001

Interleukin-15 expression in cutaneous T-cell lymphoma (mycosis fungoides and Sézary syndrome).

BACKGROUND: Cytokines are of potential importance in the pathogenesis of cutaneous T-cell mediated disorders, including cutaneous T-cell lymphoma (CTCL). OBJECTIVES: To compare interleukin (IL)-15 expression in certain inflammatory cutaneous diseases, with that in CTCL (mycosis fungoides and Sézary syndrome). METHODS: IL-15 mRNA and protein expression were examined by in situ hybridization and immunohistochemistry, respectively, on formalin-fixed, paraffin-embedded biopsies of normal human skin, atopic dermatitis, psoriasis, parapsoriasis and CTCL. RESULTS: Despite similar expression of IL-15 mRNA, we found differences in IL-15 protein expression between normal human skin, atopic dermatitis and psoriasis on the one hand, and parapsoriasis and CTCL on the other. IL-15 protein expression was not detected in normal human skin, atopic dermatitis or psoriasis, but was detected, mainly at low levels but in a few patients at higher levels, in epidermal keratinocytes in parapsoriasis, mycosis fungoides and Sézary syndrome. CONCLUSIONS: Induction of keratinocyte IL-15 expression appears to be a feature of CTCL. The factors stimulating such an expression remain unknown.

Antineoplastic Agents↗
PubMed2000

Temporal trends in survival after surgical resection of localized non-small cell lung cancer.

To test whether modern preoperative staging modalities and perioperative care improve survival after resection of localized non-small cell lung cancer (NSCLC), we retrospectively reviewed outcomes of 454 patients with NSCLC resected from 1947 through 1969 (designated pre-1970 cases), and 540 patients with cancers resected from 1981 through 1994 (designated post-1980 cases). Mean ages, histological subtypes, surgical stages, and types of surgical procedures differed significantly between the two groups. Compared with pre-1970 cases, post-1980 cases were older, had more adenocarcinoma and less squamous cell carcinoma, and had lesser proportions of advanced stage disease. Postoperative (day 30) mortality was significantly higher for resections of localized (stages 1 and 2) NSCLC prior to 1970. For patients surviving at least 30 days after surgery, subsequent survival after resection of localized NSCLC differed minimally between pre-1970 and post-1980 groups. We conclude that perioperative mortality after resection of localized NSCLC improved, but subsequent postoperative survival for these patients did not significantly improve over the 45-year period studied.

Aged↗
PubMed2000

Zinc, copper and manganese enhanced keratinocyte migration through a functional modulation of keratinocyte integrins.

The migration of keratinocytes plays an important role in the re-epithelialization of cutaneous wounds. Zinc, copper and manganese are used in vivo for their healing properties and their mechanism of action is still only partially known. Thus, they have been shown both to promote keratinocyte proliferation and to modulate integrins expression. The aim of this study was to determine if trace elements induce an increase of the migration of keratinocytes and if this effect is related to the modulation of integrins. Two independent migration assays were used to study keratinocyte migration: the scratch assay using normal human keratinocytes and the modified Boyden chamber using HaCaT cells. Inhibition studies using function-blocking antibodies directed to alpha3, alpha6, alpha(v) and beta1 subunits were performed to investigate the modulator effect of trace elements on integrin function. In this way, zinc and copper gluconates increased alpha3, alpha(v) and beta1 function whereas manganese gluconate seems mainly able to modulate the function of alpha3 and beta1. The stimulating effect of these trace elements on keratinocyte migration does not appear related to alpha6 subunit. Thus, zinc, copper and manganese enhanced keratinocyte migration and one of the mechanisms was going through a modulation of integrin functions.

3T3 Cells↗
PubMed2000

Use of a single coil transvenous electrode with an abdominally placed implantable cardioverter defibrillator in children.

While transvenous defibrillator electrode placement avoiding a thoracotomy is preferable, electrode size, a large intercoil spacing, and the need for subclavicular device placement preclude this approach in most children. We investigated a single RV coil to an abdominally placed active can ICD device. Five children ages 8-16 years (weight 21-50 kg, mean 35 kg) underwent ICD placement. Placement of a single coil Medtronic model 6932 or 6943 electrode was performed via the left subclavian vein approach and the electrode positioned in the RV apex with the coil lying along the RV diaphragmatic surface. The ICD (Medtronic Micro Jewel II model 7223 Cx) was implanted in a left abdominal pocket with the lead tunneled from the infraclavicular region to the pocket. Implant DFTs were < or = 15 J using a biphasic waveform. DFTs rechecked within 3-month postimplant were unchanged. Lead impedance at implant ranged from 38 to 56 omega, mean 51 omega. Follow-up was 3-21 months (total 82 months) with no electrode dislodgment, lead fractures, or inappropriate discharges. Two of the five patients have had successful appropriate ICD discharges. Transvenous ICD electrode placement can be performed in children as small as 20 kg with the device implanted in a cosmetically acceptable abdominal pocket that is well tolerated. Excellent DFTs can be achieved. This approach avoids a thoracotomy in all but the smallest child, does not require subclavicular placement of the device, and avoids use of a second intravascular coil.

Abdomen↗
PubMed1999

Natural splicing of exon 2 of human interleukin-15 receptor alpha-chain mRNA results in a shortened form with a distinct pattern of expression.

We report the existence of eight different interleukin-15 receptor alpha-chain (IL-15Ralpha) transcripts resulting from exon-splicing mechanisms within the IL-15Ralpha gene. Two main classes of transcripts can be distinguished that do or do not (Delta2 isoforms) contain the exon 2-coding sequence. Both classes were expressed in numerous cell lines and tissues (including peripheral blood lymphocytes) at comparable levels and could be transcribed in COS-7 cells, and the proteins were expressed at the cell surface. Both receptor forms displayed numerous glycosylation states, reflecting differential usage of a single N-glycosylation site as well as extensive O-glycosylations. Whereas IL-15Ralpha bound IL-15 with high affinity, Delta2IL-15Ralpha was unable to bind IL-15, thus revealing the indispensable role of the exon 2-encoded domain in cytokine binding. A large proportion of IL-15Ralpha was expressed at the nuclear membrane with some intranuclear localization, supporting a potential direct action of the IL-15.IL-15Ralpha complex at the nuclear level. In sharp contrast, Delta2IL-15Ralpha was found only in the non-nuclear membrane compartments, indicating that the exon 2-encoded domain (which is shown to contain a potential nuclear localization signal) plays an important role in receptor post-translational routing. Together, our data indicate that exon 2 splicing of human IL-15Ralpha is a natural process that might play regulatory roles at different levels.

Animals↗
PubMed1999

Cost of antimicrobial treatment for nosocomial infections based on a French prevalence survey.

An estimate of the antibiotic cost of nosocomial infections (NI) was made in a university hospital group based on data collected in adult inpatients enrolled in the French national prevalence survey in 1996. Among the 6839 study patients, 636 (9.3%) presented with at least one NI, of these, data on antimicrobial treatment were available for 480. The overall daily antibiotic cost was estimated between FF 49,439 and 103,526, resulting in FF 103 to 216 per infected patient. The most expensive antibiotic treatment was prescribed in intensive care patients, for pneumonia for device-related NI, or for multi-resistant bacterial infections. Non-documented NI represented about 20% of the overall antibiotic cost. Beta-lactam antibiotics, especially third generation cephalosporins, and parenteral fluoroquinolones were the most expensive antimicrobial drugs. The cost of antibiotic treatment for NI represents a significant part of hospital expenditure that should be reduced by better control of highly expensive prescriptions.

Adolescent↗